Gardner Denver RHC Series, Instruction Manual

19

TROUBLE SHOOTING GUIDE

 SYMPTOM / FAULT

POSSIBLE CAUSES

CORRECTIVE ACTION

Low refrigerant head
pressure

Compressor flooding

System Noises

Compressor will not
unload

Compressor will not load

Rapid Unloader Cycling

Cold Compressor
(Cylinders and Crankcase
Sweating

Low Crankcase Oil Level

High Crankcase Tempera-
ture (should be 100

°

F/38

°

C

to 130

°

F/55

°

C at seal

housing).

1.  Water-cooled units - Excessive water flow

Adjust water regulating valve.

     through condenser
2.  Suction shutoff valve partially closed

Open valve.

3.  Leaky compressor suction valves

Examine valve discs and valve seats;

replace if necessary.

4.  Worn piston rings

Replace if worn.

1.  Defective or improperly set expansion

Reset to 3

°

F/1.7

°

C superheat.

     valve
2.  Defective or improperly set liquid

Reset to 65

°

F/18.3

°

C return gas

     injection valve

temperature.

1.  lnsufficient clearance between piston and

Replace defective parts.

     valve plate
2.  Unit foundation improperly isolated

Isolate foundation.

3.  Improper support or isolation of piping

Use correct piping techniques, and
support piping with suitable hangers.

4.  Slugging due to refrigerant feed back

Check expansion valve setting; check
sensor bulb for looseness and correct
location.

5.  Piping vibration

Support pipes as required, check pipe
connections.

6.  Hissing (insufficient refrigerant flow thru

Reclaim refrigerant, replace strainer,

     expansion valves or clogged liquid line

and recharge with the proper amount of

     strainer)

refrigerant.

7.  Hot gas by-pass valve chattering

The chattering noise is normal and
does not affect the operation of the unit.

1.  Capacity control valve inoperative

Repair.

2.  Unloader solenoid stuck

Repair.

3.  Unloader solenoid coil defective

Replace.

4.  Hot gas by-pass valve set too high or

Reset or repair.

     sticking

1.  Capacity control valve stuck open

Repair or replace.

2.  Unloader solenoid stuck

Repair.

3.  Foaming in crankcase due to refrigerant

Check expansion valve, and piping.

     flooding

1.  Excessive fluctuation in suction pressure

Repair expansion valve.

2.  System load fluctuating

Stabilize load.

1.  Liquid carry-over from evaporator

Check refrigerant charge, expansion
valve, and desuperheating valve.

1.  Oil return screen clogged

Clean.

2.  Freon leak

Repair leak.

1.  Desuperheating valve is out of adjustment

Check operation and adjust.

2.  Liquid line strainer clogged

Clean.

3.  Excessive superheat

Reset expansion valve.

4.  Discharge temperature of 275

°

F/135

°

C

Check unit application.

5.  Leaking suction or discharge valves

Replace.

6.  Defective liquid injection valve.

Repair.